Josh Powell in court in 2010. (Photo via Creative Commons)

The Pierce County Sheriff's Department said Monday that there's increasing evidence that Josh Powell, the man believed to set fire to his own home, killing himself and his two sons, planned the fire.

Authorities released more information behind Powell's actions leading up to the gas explosion that destroyed his home and killed him and his two sons.

From the Los Angeles Times:

In the first detailed hints of what preceded Sunday's fire, Pierce County Sheriff's Det. Ed Troyer also said that Powell sent a series of relatively detailed emails minutes before the conflagration to family members and his pastor.

In the communiques -- sent too late for anyone to avert the disaster -- Powell gave some hints of why he had made his decision and logistical details about what others should do afterward, icluding how to shut off the utilities at his rented house.

"Some people got a longer one about what to do, how to shut off utilities and how to take care of some final business," Troyer, speaking at a news conference, said of the emails, which he said were sent just "minutes" before the conflagration.

"There was nobody that we've been able to determine that would have had any type of notice, to be able to do anything about it," he said. "The only thing we've gotten is, 'I'm sorry, I can't live without my boys,' and that's it. Nothing any more detailed than that."

Media outlets also reported that Powell was calm in the week leading up to the incident.

From ABC News:

Just a week before the explosion, Powell had told ABC News he was optimistic about the future and was looking forward to a day when he would regain custody of his boys.

Powell spoke with ABC News shortly after a court hearing Wednesday in which he was ordered to undergo psychosexual testing before he could regain custody of his sons.

Authorities also indicated that they found two 5-gallon gas cans in the home after the blaze was extinguished. One was found next to the bodies of Josh Powell and his two boys, who were found in the center of the house. Authorities said autopsies would be performed on Monday.